Gas turbines are continuously being modified to increase efficiency and decrease cost. One method for increasing the efficiency of a gas turbine includes increasing the operating temperature. Increases in operating temperature result in more extreme operating conditions which has led to the development of coating systems designed to increase the heat tolerance of the turbine components and protect the turbine components from reactive gases in the hot gas path of the gas turbine. The temperature tolerance of a turbine component may also be increased through the use of cooling channels. Cooling channels are also coated to increase heat tolerance and protect from reactive gases in the hot gas path.
Coating the internal surfaces of cooling channels and other internal surfaces within a gas turbine component may be complicated by factors such as small apertures accessing the internal channels of the component, which may be easily blocked by coating residue. Removal of such blockages is difficult and costly. Further, current coating methods are inefficient, wasting significant amounts of coating material, may require the use of argon, which increases cost, and may contaminate furnace chambers used in the coating process with the coating material, requiring periodic decontamination.